The government published building regulation changes for England in late 2021. These will come into effect on June 15th, 2022.
Replacement UPVC windows in existing dwellings
This market sector will now be required to meet a minimum WER 'B' rating or 1.4W/m2.K whole window U-value, including glazing.
To achieve this, most windows must swap aluminium spacer bars for warm edge spacer bars. A typical IGU would be made up of the following:
4mm clear glass / 16 or 20mm warm edge spacer & Argon filled cavity / 4mm soft coat low e glass
This is virtually 90% of our current production, is almost standard, and generally achieves WER band 'A' in most window systems.
Timber windows can have an overall U-value of 1.6W/m2.K and may use the same unit makeup.
New build dwellings
Here, the performance requirements are slightly different, but a 1.2W/m2.K overall U-value has been put forward, which will be the primary qualifying criteria. This will require most UPVC windows to be glazed with a better-performing IGU. Most systems should be able to meet the new legislation using a 1.0 glass. A typical IGU would be:
4mm clear glass / 16 or 20mm warm edge spacer & Argon filled cavity / 4mm Planitherm One (or equivalent low e)
*All windows should be calculated using the IGU performance to determine if the regulations can be met.
Regency stocks both standard soft coats—we use Planitherm Total + FG and Planitherm One. These will help achieve the required U-values.
The most significant change will be that aluminium spacer bars will no longer meet the requirements and will be phased out as the June deadline approaches. Aluminium spacer bars are currently imported into the UK, and due to component suppliers not wishing to be left with unwanted stock, the discontinuation of aluminium spacers could well accelerate and happen before the rules change.
More information can be found using the link below.
